Founded in 1993 by brothers Tom and David Gardner, The Motley Fool helps millions of people attain financial freedom through our website, podcasts, books, newspaper column, radio show, and premium investing services.

A Mass-Market, 3D-Printed Athletic Shoe Is Coming, and This Upstart's Technology Is to Thank

3D Systems is left in the dust: Carbon is on track to dominate this market.

Athletic shoe giant adidas AG(NASDAQOTH:ADDYY) announced last week that it's partnering with venture-backed 3D printing upstart Carbon to manufacture athletic shoes with 3D-printed midsoles for the mass market. The first shoe in the Futurecraft 4D line will be a running shoe, which customers will eventually be able to order with custom midsoles.

With this partnership, adidas sprints past athletic shoe industry leader Nike, Under Armour(NYSE:UA)(NYSE:UAA), and others to become the first in the industry to announce a plan with concrete timetables to produce 3D-printed shoes for the mass market.

On the 3D printing end, this partnership propels Carbon way ahead of current leader 3D Systems (NYSE:DDD) in the 3D-printed shoe space. Moreover, Carbon is on track to become the tech supplier behind a momentous 3D printing industry record: Once production hits full scale, the Futurecraft 4D will be the highest-quantity mass-produced 3D-printed product ever!

Here's what you should know.

The name Futurecraft 4D represents adidas bringing 3D printing in its industry into a new dimension. Image source: adidas.

Adidas' mass-market 3D printed shoe plans

Adidas' new running shoe will be the world's first athletic footwear -- or any footwear, for that matter -- with midsoles produced by Carbon's Digital Light Synthesis, enabled by its proprietary Continuous Liquid Interface Production technology.

Futurecraft 4D's midsole -- which is the part of a shoe that provides support and cushioning -- is made of a blend of polyurethane and adidas' proprietary ultraviolet light-curable resin, which it developed with Carbon. It's a durable elastomer (a polymer with properties like natural rubber) that's 3D-printed in a lattice structure, which makes it supportive, yet lightweight. Adidas designed the midsole using nearly two decades of athlete running data. The shoe's uppers will be made of adidas' proprietary Primeknit and its outsoles of a reportedly superior-grip rubber compound.

Adidas plans to produce 300 pairs of Futurecraft 4D for folks close to the company this month, 5,000 pairs for retail sale later this year, more than 100,000 pairs by the end of 2018, and then rapidly scale to millions of shoes per year. The company didn't provide a price for the shoes. Once production ramps up, the shoes will be made at adidas' "Speedfactories."

3D-printed athletics shoes are more than just a novelty item. Even without custom midsoles, they can provide real benefits to the consumer, as well as to the company producing them. 3D printing opens up an immense range of design possibilities, some of which have performance implications. The geometries that have so far made appearances on 3D-printed midsoles -- adidas' and Under Armour's lattices and New Balance's honeycomb -- can't be made using traditional manufacturing techniques. Moreover, 3D printing allows for producing a shoe with variable properties across the midsole, whereas this is impossible to do with a single injection-molded midsole. Athletic shoe companies have to piece together components if they want properties to vary across a midsole. This isn't just labor-intensive, it also introduces possible points of failure where the components are assembled.

Adidas didn't specify the logistics behind eventually offering the shoe with midsoles customized to meet an individual's unique needs. However, when the company unveiled its Futurecraft concept for 3D-printed shoes in 2015, it said it envisioned customers having their feet scanned at one of its retail stores to produce a digital 3D model and running on a treadmill to gather biomechanical data.

A Futurecraft 4D midsole being 3D-printed. Image source: adidas.

Carbon and its speedy CLIP 3D printing technology

Privately held Carbon is little-known among the general public, but the Silicon Valley-based 3D printing company has captured the attention of many in the tech world since the TED 2015 conference. That's where Co-founder and CEO Joseph DeSimone, PhD, wowed the audience when he unveiled and demonstrated the company's proprietary Continuous Liquid Interface Production (CLIP) technology for 3D printing of polymers.

Carbon claimed at the time that CLIP was about 25 to 100 times faster than the leading 3D printing techs. This was exciting because speed has been one of the major obstacles preventing 3D printing from moving beyond a primarily prototyping and very short-run production technology into one that's also suited to a wider range of manufacturing applications.

Carbon touts that CLIP jumps several other hurdles that have been holding 3D printing back from disrupting traditional manufacturing. The technology reportedly opens up an immense range of new materials possibilities, and it can produce objects with surface qualities and mechanical properties on par with injection-molded plastics.

CLIP works by harnessing ultraviolet (UV) light and oxygen to "grow" polymer parts continuously from a pool of liquid resin. It can be thought of as a close cousin of stereolithography (SLA), which is also a photopolymerization process that uses UV light to solidify liquid resin into the desired object. SLA was invented by 3D Systems; 3D Systems' prime rival Stratasys also has a well-established photopolymerization technology called PolyJet.

As for Digital Light Synthesis, the two partners explain in the press kit that it's a broader term than CLIP. Don't sweat the terminology; my guess is that Digital Light Synthesis is now making its appearance in Carbon's lingo because it's easier for the layperson to understand and sounds sexier than Continuous Liquid Interface Production.

Just last month, Carbon launched SpeedCell, a system of connected products for manufacturing applications. SpeedCell's first available components are the M2 3D printer, which has a volume twice as large as Carbon's flagship M1 launched a year ago, and the Smart Part Washer for cleaning and finishing of parts.

Carbon has raised $221 million from top venture capital firms and the VC arms of corporate titans such as General Electric and Google parent Alphabet. In addition to adidas, its big-name partners include Ford, Johnson & Johnson, BMW, and UPS.

Image source: adidas.

Carbon sprints past 3D Systems in the 3D-printed athletic shoe race

Certainly, partnering with the No. 2 player in the $81.9 billion global athletic shoe market is a big coup for Carbon. adidas is going to need a bunch of Carbon's 3D printers and related equipment -- which it distributes via subscriptions only -- if it plans to eventually produce millions of pairs of Futurecraft 4D shoes per year.

It currently takes a Carbon 3D printer one-and-a-half hours to churn out one midsole, though adidas and Carbon are working to develop new machinery that will reduce this time to 20 minutes. At a production speed of 20 minutes per midsole, adidas will be able to produce 72 midsoles per day on one 3D printer, assuming it's running continuously around the clock (a liberal assumption). It's easy to work through the numbers to see that Carbon is on track to generate some big money from this partnership.

Prior to the Carbon-adidas partnership announcement, 3D Systems, with its selective laser sintering (SLS) technology, was the undisputed leader among 3D printing companies in the 3D-printed athletic shoe realm. However, this technology -- which uses a laser to fuse powders -- is much too slow to use for more than prototyping or making very limited edition athletic shoes with 3D-printed midsoles. For instance, it took Under Armour "under 24 hours" to print one midsole using SLS, according to Business Insider.

Both privately held New Balance and Under Armour have released very limited edition shoes with 3D-printed midsoles that were made by SLS. 3D Systems is New Balance's exclusive partner in its 3D-printed shoe initiatives. Last April, the Boston-based company released 44 pairs of the $400 Zante Generate, the world's first running shoe with a full-length 3D-printed midsole. Just prior to New Balance's launch, Under Armour launched its first UA Architech, which it touted as being the world's first multipurpose training shoe with a 3D-printed midsole. The Baltimore-based sportswear company released 96 pairs that sold out online in less than 20 minutes at $300 a pop. While Under Armour used 3D System's SLS tech to produce the shoes, there was no indication that the two are partnering in any formal way.

But this race is a marathon

Carbon is now leading the pack in the 3D-printed athletic shoe race, but this race is a marathon. Stratasys is still at the starting line. HP Inc., with its Nike partnership, might eventually make a move. 3D Systems seems the most likely to challenge Carbon. Last month, the company launched its super-fast 3D-printing production platform called Figure 4, which is powered by a form of SLA. 3D Systems' new technology sounds a lot like Carbon's CLIP, so it might also be a good fit (pun intended) for printing elastomeric midsoles.

You can't buy stock in Carbon, as it's privately held, but in my opinion it's only a matter of time before this fast-growing company goes public.

Suzanne Frey, an executive at Alphabet, is a member of The Motley Fool's board of directors. Beth McKenna has no position in any stocks mentioned. The Motley Fool owns shares of and recommends GOOG, GOOGL, Ford, Johnson & Johnson, Nike, and Under Armour (A and C shares). The Motley Fool owns shares of General Electric. The Motley Fool recommends 3D Systems, BMW, and Stratasys. The Motley Fool has a disclosure policy.